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Short circuit connecting preamp with amp (RCA)

it will need figuring out how the chassis has power on it . some good pictures inside where the power wire goes in might help .

logically it has to be the one without the ground causing the breaker to operate .if it was the grounded one it would trip plugged in on its own .
 
I found that the power amp is gone... :( I tried to power it up with ( with a bulb light tester) And the bulb get full bright. The short have killed somthing inside. Im going to check the output transistors. In this type of failieurs do i have to check some specific parts?

Thanks for the help , and sorry for bothering.
 
elgrillo said:
I found that the power amp is gone... :( I tried to power it up with ( with a bulb light tester) And the bulb get full bright. The short have killed somthing inside. Im going to check the output transistors. In this type of failieurs do i have to check some specific parts?

Thanks for the help , and sorry for bothering.
Click to expand...

I hope tomorrow i can find and replace the fail component , and light it up again, and find were the leak of Ac is.

I take out the left chanel power transistors, and check them, thay are Ok , but the Mica washers are not nice, It coud be that the AC comes from the transistors?

Thanks
 
maybe the original fault is the preamp . its hard to say really
check the dc volts at the rca outputs on preamp .
am thinking voltage from preamp may have damaged power amp . its only a thought though .
what wattage lamp is in your tester ?
 
petehall347 said:
maybe the original fault is the preamp . its hard to say really
check the dc volts at the rca outputs on preamp .
am thinking voltage from preamp may have damaged power amp . its only a thought though .
what wattage lamp is in your tester ?
Click to expand...

The lamp is 120w (AC outlet 230 v France)

To check dc in pre amp output , I have to put the red lead to the inner RCA and the black one in the outer RCA ? In both channels ? like a dc offset but in the RCA ?
 
Something strange?

Hi, today I found something strange in the preamp. I put the Multimeter in conectivity mode and put the read lead in the iner RCA , and the black lead in the outer RCA , and i got a a beep . is that normal?

Then i checked the others rca's and found that in the Tune, phono 1 , and phono 2, the same beep as in the preamp output.

In Aux, tap 1 and tape 2 ( in and out ) no beep at all?

is that right?
 
petehall347 said:
maybe they are shorted internally to stop any crossover of the signals when that input isn't in use
Click to expand...

Well i have masur DC and Ac in the preamps outputs. This are the results:

Left chanel: AC ( multmeter in 2 ) .064V
Left chanel: DC ( multmeter in 200m) 00.0v

Right chanel: AC ( multmeter in 2 ) .072V
Left chanel: DC ( multmeter in 200m) 00.0V

So it looks like the preamp is not the problem?
 
elgrillo said:
Well i have masur DC and Ac in the preamps outputs. This are the results:

Left chanel: AC ( multmeter in 2 ) .064V
Left chanel: DC ( multmeter in 200m) 00.0v

Right chanel: AC ( multmeter in 2 ) .072V
Left chanel: DC ( multmeter in 200m) 00.0V

So it looks like the preamp is not the problem?
Click to expand...

Well if this is Ok , I think next step is to put running the power amp again , and do the chassis to chassis test for DC and AC.
 
petehall347 said:
yes give it a try
Click to expand...

Peter, just a question, i have a marantz 250 that i was afraid to hook up with the 3200 after the problem with the marantz 32. Do you think im save ? ro do I need to do other tests to the preamp?

I just want to have some music while repairing the 32.

Thanks a lot for the help, as soon I put to work again the marantz 32, I will make the chassis to chassis test and post the updates.

Thanks again!
 
yes try the chassis to chassis test first with the 250 and 3200 to be on the safe side ..sometimes logic theory doesn't work in practice .
i am thinking it will be ok but do the test anyway .
does the 250 have an earth to the power plug ?
 
petehall347 said:
yes try the chassis to chassis test first with the 250 and 3200 to be on the safe side ..sometimes logic theory doesn't work in practice .
i am thinking it will be ok but do the test anyway .
does the 250 have an earth to the power plug ?
Click to expand...

Nope, again an early marantz , this one with the original plug, but no earth. :no:
 
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